An active fixation lead may utilize a helix at its distal end for fixation into the heart tissue. The lead may have a lead connector end at its proximal end that includes a contact pin that is welded to an inner coil, which extends through the lead body and is welded to the helix at the distal end of the inner coil. The helix, inner coil and contact pin are rotatable as a unit within the lead body.
In order to extend the helix from the distal end of the lead body and anchor the helix into to heart tissue, a clip-on tool or implant tool is used to rotate the contact pin relative to rest of the lead connector end and the lead body. The effectiveness of this helix fixation method varies based on the number of contact pin rotations. For example, insufficient rotation can result in inadequate helix fixation to the heart tissue, and excessive rotation can damage the weld joints or result in perforation of the heart wall.
There is a need in the art for a lead delivery device that facilitates proper fixation of the helix to heart tissue. There is also a need in the art for a method of achieving proper fixation of the helix to heart tissue.